> Worried in economic terms though

The techbros who publicly fret about population decline are worried about white population decline. Population decline in the West is easily managed by letting more non-Western people in. It's not like Germany/UK/US/France have a monopoly on intelligence and hard work.

Globally small economies outside the West don't depend on continuous growth, and a "soft landing" where population declines but gradually and possibly asymptotically is not a threat to the economy.